The amended lawsuit was filed in California federal court yesterday, according to The Hollywood Repoter. Shearer filed a fraud and contract-breach lawsuit last October. The original damages set at $125 million have been increased to $400 million.

The three actors, along with director Reiner, state they were given only $81 in merchandising income and $98 in music sales over the past few decades. They also claim to have not received accounting statements for the past three years in regards to This Is Spinal Tap.

"They allege Vivendi has engaged in 'anti-competitive and unfair business practices and has abandoned its obligations to enforce intellectual property rights,'" The Hollywood Reporter notes, "and bringing contract claims, they are seeking to regain rights to the property and collect compensatory and punitive damages."

The Hollywood Reporter speculates Guest, McKean and Reiner's participation now fixes a flaw in the original suit that named Shearer's Century of Progress Productions as the only plaintiff. Defendants could claim that "Shearer didn't have standing to contest contractual obligations."

The amended suit includes Spinal Tap Productions, which is owned by Shearer, McKean, Guest and Reiner, and states that, according to a 1982 agreement, they are entitled to 40 percent of net receipts.

“Fair reward for artistic endeavor has long been raised by those on the wrong end of the equation," Reiner said in a statement. "What makes this case so egregious is the prolonged and deliberate concealment of profit and the purposeful manipulation of revenue allocation between various Vivendi subsidiaries – to the detriment of the creative talent behind the band and film."

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